Gastric POCUS, 3-Part Episode

Hyperkalemia can be a life-threatening condition with the potential to deteriorate to cardiac arrest. While there are multiple interventions that can reduce serum potassium, the administration of calcium has the quickest onset and provides the greatest initial protection to stabilize cardiac electrical membrane potentials and avoid arrhythmias. Calcium will act within just a few moments. Calcium chloride is more irritating to peripheral blood vessels and thus should be administered via central venous access, or diluted. Calcium gluconate can be given peripherally without dilution but a larger dose is needed to achieve the same therapeutic effect as calcium chloride because calcium gluconate contains less calcium. The acute treatment of hyperkalemia involves shifting potassium to the intracellular space through actions such as hyperventilation and administration of sodium bicarbonate, dextrose and insulin, albuterol, and epinephrine. These methods are effective but may require 10-20 minutes for onset. Increasing potassium excretion through the kidneys is also possible with administration of furosemide, but this also requires time to accomplish. Elimination of potassium by gastrointestinal resin exchange may be used in more chronic circumstances. Hyperkalemia greater than 6.5 mEq/L, in the context of anuric renal failure, is an indication for acute renal replacement therapy.